tag:blogger.com,1999:blog-6244999628674918029.post3188136168254753389..comments2024-03-28T03:06:18.182-05:00Comments on Bayou Renaissance Man: Tragic crash at Russian air showPeterhttp://www.blogger.com/profile/10595089829300831372noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-6244999628674918029.post-65382922712871655072015-08-03T12:05:40.164-05:002015-08-03T12:05:40.164-05:00Either a combining gearbox or tail rotor shaft fai...Either a combining gearbox or tail rotor shaft failure is what it looks like... Loss of tail rotor authority comes as he pulls up, and you can see the tail rotor is windmilling as he descends... No forward speed to try to do a run on, they were basically screwed as I didn't see an autorotation attempt per se...Old NFOhttps://www.blogger.com/profile/16404197287935017147noreply@blogger.comtag:blogger.com,1999:blog-6244999628674918029.post-45352889474254127882015-08-02T23:17:51.609-05:002015-08-02T23:17:51.609-05:00Peter, I think it more likely that there was a fai...Peter, I think it more likely that there was a failure of the drive system. Helicopters are designed with the tail rotor beyond the reach of the main blades to prevent the two ever coming into contact. The tail rotor should be spinning at ten times the rpm of the main rotor, instead it is windmilling. There is a drive shaft from the rear of the transmission, supported by several bearings in the tail boom, an angled gearbox, a short shaft upwards and finally the tail rotor gearbox. A failure in any of those components and the pilot has only one choice - autorotate straight ahead. Unfortunately the failure occurred in a vertical climb leaving few options.<br /><br />The tail rotors of the Hughes Apache, Bell 429 and this Mil helicopter have four blades that have an uneven split between them for noise reduction. It's supposed to look like a squashed X rather than a + sign. <br /><br />Al_in_OttawaAnonymousnoreply@blogger.com